Science Unit 3 Lesson 7 Flashcards
What are fossil fuels?
Fossils fuels were formed from the remains of plants and animals that lived long ago. They were formed by once living organisms. When these carbon-rich fuels burn, they give off carbon dioxide as a waste gas. Carbon dioxide is a greenhouse gas that traps heat in Earth’s atmosphere
How does coal, oil, and natural gas form?
Fossil fuels are the remains of plants and animals that lived and died millions of years ago. Over those millions of years, coal, oil, and natural gas formed when pressure and heat transformed those once-living organisms into fossil fuels.
What is the main source of carbon dioxide?
Combustion of fossil fuels is also the main source of carbon dioxide, a greenhouse gas largely responsible for the unnatural warming of Earth’s atmosphere
What percent of the energy we use in the US comes from fossil fuels?
About 80 percent of the energy we use in the United States comes from fossil fuels.
What are the 3 main fossil fuels?
Coal
Oil
Natural Gas
How does Coal form?
Coal is formed from plants that died in swampy forests, and were then buried by layers of sediment. Over hundreds of millions of years, heat and pressure transformed the buried plants into coal. Because coal produces more carbon dioxide and other harmful pollutants than the other major fossil fuels, there are now efforts to limits its use.
How does oil and natrual gas form?
Oil and natural gas both form from the remains of tiny marine plants and animals. After they died, the organisms accumulated at the bottom of seas where sand and mud buried them. As the layers thickened on top of them, intense heat and pressure changed them into petroleum and natural gas. Oil and natural gas can form together or separately. Crude oil as it comes out of the ground is refined into many products, such as gasoline, heating oil, and diesel fuel.
Explain Oil Shale and Tar sands?
Other fuels include oil shale and tar sands. They produce carbon dioxide when burned, just as other fossil fuels do. The advantage of these “other” fossil fuels is that some of the world’s largest deposits are in the U.S. and Canada. There are environmental challenges of using these fossil fuels. Extracting and processing oil shale and tar sands require large quantities of freshwater and energy and produce toxic substances.
What are the benfits of greenhouse gases?
the greenhouse gases in Earth’s atmosphere keep the planet warm enough to support life. Greenhouse gases allow short-wavelength solar energy (such as visible light and ultraviolet) to pass through the atmosphere and strike Earth’s surface. The surface then re-radiates that energy at a longer-wavelength, infrared energy or heat. The greenhouse gases absorb some of this longer-wavelength energy instead of allowing it to leak out into space.
Greenhouse gases keep the Earth’s and what temperatrue, and how would Earth’s temperature be without these gases?
The greenhouse gases keep the planet’s average temperature at about 15.6°C (60°F). Without these gases, Earth’s average temperature would be near freezing. The way greenhouse gases affect Earth’s temperatures is called the greenhouse effect.
About what percentage are greenhouse gases in Earth’s atmosphere?
Although greenhouse gases are important, they make up less than one percent of Earth’s atmosphere. Still, they have properties that give them the ability to act as a warming blanket around the planet.
Why doesnt water vapor have the same negative effects of Carbon dioxide?
Although water vapor is more abundant than carbon dioxide in the atmosphere, the amount of water vapor remains relatively consistent, so it does not change climate
Of all greenhouse gases whichminfluences the greenhouse effect and climate change.
. Of all greenhouse gases, the effect of the increase of carbon dioxide in the atmosphere is the factor that most influences the greenhouse effect and influences climate change.
What was the carbon dioxide level compared to now and the before the start of the Industrial Revolution? Is it higher than any other time in human history?
Just before the start of the Industrial Revolution the concentration of carbon dioxide in the air was about 280 parts per million (ppm). Today it is more than 400 ppm. Yes, this is higher than at any other time in human history.
How and why did carbon dioxide increase so much in the atmosphere?
After the start of the Industrial Revolution in the mid-1700s, machines began to replace animal and human power for doing work. Most machines burned fossil fuels, especially coal. The rate at which carbon dioxide entered the air rose sharply, and is still rising.
Deforestation has also increased the atmosphere’s load of carbon dioxide. The trees in forests remove carbon dioxide from the atmosphere during photosynthesis. Loss of forests allows much of that carbon dioxide to remain in the atmosphere.
